Abstract
As reported in the previous paper of the series, it was recognized in our previous studies on the electrolytic concentration of sea water with porous ion exchange membranes, that the results of the concentration were influenced by the amount of brine to be produced.
This paper presents a study of effects of current density on the concentration of brine under the condition that the amount of brine was made constant, and the following results were obtained.
1) The concentration of brine increases in accordance with an increase of the current density.
2) Furthermore, the amount of produced salt increases as the current density increases. However, at a high current density, an anticipated yield of the salt can not be obtained, and therefore the current efficiency apparently decreases.
3) The voltage of cell increases in proportion to the current density, while the amount of electric power increases as the current density increases.
4) From the above results, it is concluded that the utilization of porous membranes for the electrolytic concentration of sea water is not suitable method from the viewpoint of industrial use, because it is difficult to produce brine of high concentration.
